142 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[April, 



THE PYRAMIDS OF GIZEH. 



At the Royal Institute of British Architects, on the 6th ultimo, a letter 

 was read from Mr. Perring, containing some remarks on the great Pyramid, 

 accompanied by a model. 



" The model is on a scale of 30 ft. in the inch, and represents the pyramid 

 in its original condition, — that is, immediately after the sarcophagus was 

 placed therein, and before the passages were filled with stone blocks closing 

 the entrance. From an examination of the ancient Egyptian cubit now 

 remaining, I deduced the length to be 1-713 English feet, divided into four 

 palms, each of seven digits. This measure, when applied to the pyramids, 

 agrees as closely as to render its correctness certain, and I proceed to men- 

 tion a few of the more obvious results in the edifice before us. The base 

 covered a square of 448 cubits on each side, which, from a statement of 

 Pliny, I take to have been equal to eight Egyptian jugera, or acres ; and this 

 supposition is somewhat confirmed by finding the second pyramid would then 

 cover seven, and the third, one and three quarters of these supposed jugera, 

 and so on with the other pyramids of Egypt. The height of the great pyra- 

 mid appears to have been 230 cubits, being a proportion of height to side of 

 base of 5 to 8 ; and I may here mention that several other pyramids have 

 the same proportions. This gives the following ratio on a direct section : 

 As half the base is to the perpendicular height, so is the apotheme, or slant 

 height to the whole base ; or for each side it may be thus stated as 

 Rad : Tang : : Sec : 2 Rad. 



" Sir John Herschel having the angles only of the pyramids and their pas- 

 sages before him, gave his decided opinion that they'were " not connected 

 with any astronomical fact, and probably adopted for'architectural reasons;" 

 and the knowledge of the above proportions will I think lead to the same 

 conclusion ; for with the most solid and enduring shape possible, the builders 

 obtained a mathematical symmetry which no other proportions could give. 

 Although this pyramid was nearly 480 feet in perpendicular height of solid 

 masonry, the pressure of the enormous mass is so distributed, that the lower 

 courses have only to sustain about 25,000 lb. on the square foot, whilst the 

 material is equal to at least 1,100,000 1b.; therefore it is evident that the 

 main objects of the architect— viz., stability and eternal duration— were well 

 effected. The inclination of the entrance passage of the great pyramid was 

 regulated by a proportion of 2 to 1 : that is, two feet horizontal 'to one foot 

 perpendicular. 



" The same mode of regulating the angles is observable in every instance ; 

 thus where inclined blocks were used to cover an apartment, a certain por- 

 tion of the width of the room was taken for the rise or pitch : as in the 

 queen's chamber, where the rise is a third of the width of the apartment, 

 and also the angle of the air passages leading from the king's chamber to the 

 exterior, have a rise of one perpendicular to two horizontal. From finding, 

 in even case, that the angles were thus regulated, I have come to the con- 

 clusion that the Egyptians, at the time of the erection of these mightv 

 monuments, possessed no knowledge of the division of the circle into 

 degrees, but that their angles were regulated by the proportion of base to 

 perpendicular height; in fact, the tangential measure of the angle, and not 

 its abstract measurement. That they learned to divide the circle into 

 degrees at a later period is highly probable, as thev were celebrated for their 

 astronomical knowledge. 



" In every part of the pyramids evidences of premeditated and careful de- 

 sign are apparent ; but my present purpose is to draw attention to the more 

 striking points in the great pyramid only. The situation of the apartments 

 in the pyramid appear to have been regulated as follows 



Height from base (external) to floor of passage of queen's 



chamber 



From the above to floor of king's chamber, or principal 



apartment 

 From the above to top of upper chamber . . . . . . 40 



From the above to apex of pyramid .. .. 160 



40 cubits 



Total 



280 cubits 



Making 280 cubits in perpendicular height, as above stated. The floor of 

 the subterraneous apartment was also 60 cubits below the base of the 

 pyramid." 



ROYAL COMMISSION OF FINE ARTS. 



Her Majesty's Commissioners hereby give notice : 



1. That the cartoons or drawings intended for competition, according to 

 the notices published in April and July. 1842, will be exhibited in Westmin- 

 ster Hall whither they are to be sent between the hours of 10 and 5 on anv 

 day, Sunday excepted, during the first week in June next, when agents will 



WataSSftftoTlS: them; """ D ° draWiDg WiU ^ receivedaf,er 

 A^L E ' acU c , andidate is squired to put a motto or mark on the back of his 

 hL „ m n'„ a ,, °,r nd ' t0gether with his drawing, a sealed letter containing 

 mark Zuf t?"' T 1 h,vin « ° n the °"^ de ° f its ™™ » »otto or 

 mark similar to that on the back of the drawing. The letters belonging to 



the drawings to which no premium shall have been awarded will lie returned 

 unopened. 



3. The title of the subject of each drawing, together with the quotation, 

 if any, to illustrate it, must be affixed either to the back or front of the 

 drawing. 



4. Each drawing is to be sent upon, or accompanied by, a stretching- 

 frame ; but no ornamental frames in addition to the stretching-franie will be 

 admissible. 



5. The artists or their agents may attend to examine the works sent by 

 them, and to re-stretch such drawings as shall have been detached from 

 their stretching-frames and rolled for the convenience of carriage. 



6. No drawing will be allowed to be re-touched after having been received, 

 except to repair an injury occasioned by accident, and then only by the artist 

 himself. 



.". Every possible care will be taken of the works sent, but in case of in- 

 jury or loss, the commissioners will not be responsible. 



8. All the drawings will be exhibited, and catalogues will be published. 



9. The names of the judges appointed to award the premiums will he 

 made known. 



By command of the Commissioners, 

 Whitehall, March 24. C. L. EASTLAKE, Secretrjrv. 



THE NEW HOUSES OF PARLIAMENT. 



REPORT FROM THE SELECT COMMITTEE. 



That the committee have met and considered the subject-matter to them 

 referred, and have examined witnesses, and have come to the following reso- 

 lution, viz. : That considering the great inconvenience of the present House 

 of Lords, and that such inconvenience will be greatly aggravated by the pro- 

 gress of the new buildings before the commencement of the session of 1844, 

 no delay should take place in the building and preparing the new House of. 

 Lords beyond what is absolutely required for the safety of the work ; that the 

 architect he directed so to conduct his operations as to secure the occupa- 

 tion of the new House of Lords, with temporary fittings, at the commence- 

 ment of the session of 1844 ; that in case the architect in the progress of 

 the work of the new House of Lords shall find that more time will be 

 required in consequence of any apprehension of injurious consequences to 

 the building, he shall report the same to the Commissioners of her Majesty's 

 Woods and Forests, in order that such report may be communicated to this 

 house in due time ; that it does not appear to the committee that it is 

 advisable that any alterations in the ventilation of the present House of 

 Lords, which would lead to additional expense, should be adopted ; and the 

 committee have directed the minutes of evidence taken before them to be 

 laid before your Lordships. — March 13. 



A return made to the House of Commons, published 27th ult., states that 

 the total amount already expended for building the new Houses of Parlia- 

 ment is .t'380,483 10*.; the amount voted has been £438,500, and conse- 

 quently .£58,016 10*. is in band unexpended, which will be required for 

 works now in progress of completion. It is estimated that a further sum of 

 £578,424 12f. 'Ml. will be required to complete the buildings. The total 

 amount of Mr. Barry's estimate will therefore be £1,016,924 12s. 9rf., be- 

 sides what will be required for completing the landing-places, making good 

 the pavings, furniture, and fittings, and for decorations by works of art. 



The House of Commons, on the 2 "th ult., voted an additional grant of 

 £] 1(1,000 towards the works. 



NEW INVENTIONS AND IMPROVEMENTS. 



DREDGE'S SUSPENSION BRIDGE. 



The very economical, simple, and powerful principles of the lever in the 

 construction of bridges, may be illustrated thus. A bridge is two arms 

 united at the ends of the chains, the centre, where weight begins and in- 

 creases from thence progressively, as the chains increase in magnitude and 

 power to the points of suspension. This is effected by an oblique instead of 

 a vertical connection of the platform to the main chains, which fixes all 

 horizontal force in the horizontal line, and gives to the stability of a bridge 

 the most valuable assistance, as is proved by the numerous bridges already 

 erected upon the principle in various parts of Great Britain. 



Its truth may also be easily understood by the following experiments. 

 Cut the chains in the middle and the bridge will stand as firm as ever, there 

 being no strain there; then cut the platform in the middle and it will be 

 separated into two independent brackets, each supported by the chains aud 

 the strength of the horizontal line against the abutment. The force re- 

 quired to resist this tendency, is a measure of the power conferred upon the 

 bridge, by reason of the oblique connexion of the horizontal line to the 

 chains-, independent of the advantage gained by tapering them. On the 

 other hand, cut the chains of a common bridge at the centre, it will destroy 

 the structure ; or cut the platform in the middle and leave the chains entire, 

 then it will be seen that there is no tendency of thrust against the abut- 



